Which halos host Herschel-ATLAS galaxies in the local Universe?
Abstract
We measure the projected cross-correlation between low redshift (z < 0.5) far-IR selected galaxies in the SDP field of the Herschel-ATLAS (H-ATLAS) survey and optically selected galaxies from the Galaxy and Mass Assembly (GAMA) redshift survey. In order to obtain robust correlation functions, we restrict the analysis to a subset of 969 out of 6900 H-ATLAS galaxies, which have reliable optical counterparts with r<19.4 mag and well-determined spectroscopic redshifts. The overlap region between the two surveys is 12.6 sq. deg; the matched sample has a median redshift of z ~ 0.2. The cross-correlation of GAMA and H-ATLAS galaxies within this region can be fitted by a power law, with correlation length r_0 ~ 4.63 +/- 0.51 Mpc. Comparing with the corresponding auto-correlation function of GAMA galaxies within the SDP field yields a relative bias (averaged over 2-8 Mpc) of H-ATLAS and GAMA galaxies of b_H/b_G ~ 0.6. Combined with clustering measurements from previous optical studies, this indicates that most of the low redshift H-ATLAS sources are hosted by halos with masses comparable to that of the Milky Way. The correlation function appears to depend on the 250 um luminosity, L_250, with bright (median luminosity \nu L_250 ~ 1.6 x 10^10 L_sun) objects being somewhat more strongly clustered than faint (\nu L_250 ~ 4.0 x 10^9 L_sun) objects. This implies that galaxies with higher dust-obscured star formation rates are hosted by more massive halos.
Keywords
Cite
@article{arxiv.1011.3048,
title = {Which halos host Herschel-ATLAS galaxies in the local Universe?},
author = {Qi Guo and Shaun Cole and Cedric G. Lacey and Carlton M. Baugh and Carlos S. Frenk and Peder Norberg and R. Auld and I. K. Baldry and S. P. Bamford and N. Bourne and E. S. Buttiglione and A. Cava and A. Cooray and S. Croom and A. Dariush and G. De Zotti and S. Driver and L. Dunne and S. Dye and S. Eales and J. Fritz and A. Hopkins and R. Hopwood and E. Ibar and R. J. Ivison and M. Jarvis and D. H. Jones and L. Kelvin and J. Liske and J. Loveday and S. J. Maddox and H. Parkinson and E. Pascale and J. A. Peacock and M. Pohlen and M. Prescott and E. E. Rigby and A. Robotham and G. Rodighiero and R. Sharp and D. J. B. Smith and P. Temi and E. van Kampen},
journal= {arXiv preprint arXiv:1011.3048},
year = {2015}
}
Comments
9 pages, 8 figures, 1 table, submitted to MNRAS